Acute pancreatitis is characterized by an inflammatory storm which regulatory pathways are not well known. The IL-1 cytokine family is activated early during acute pancreatitis and secretion of alarmins is speculated during pancreatic necrosis. IL-33 is a member of the IL-1 family, it can act as an alarmin and its receptor, ST2, is known to sequester MyD88 which might regulate the acute pancreatitis inflammatory storm. The aim of this study is to investigate ST2 pathway in human acute pancreatitis and in murine experimental models of acute pancreatitis.